Methyl iodide → 1-methyl-1H-1,3-benzodiazol-5-amine

HRID 2304709Notes

Reaction equation

HRID 2304709 reaction equation
[N+:1]([C:4]1[CH:12]=[CH:11][C:7]2[N:8]=[CH:9][NH:10][C:6]=2[CH:5]=1)([O-])=O.[H-].[Na+].[CH3:15]I>C1COCC1.CO.[Pd]>[CH3:15][N:8]1[C:7]2[CH:11]=[CH:12][C:4]([NH2:1])=[CH:5][C:6]=2[N:10]=[CH:9]1.[CH3:15][N:10]1[C:6]2[CH:5]=[C:4]([NH2:1])[CH:12]=[CH:11][C:7]=2[N:8]=[CH:9]1

Participants

8

Reactant 3

HCID 6328Methyl iodideHCID 71955-NitrobenzimidazoleHCID 24758Sodium hydride

Product 2

HCID 3154991-methyl-1H-1,3-benzodiazol-5-amineYield 21%HCID 136802831-Methyl-1H-benzimidazol-6-amineYield 11%

Reagents, catalysts & solvents 3

HCID 23938PalladiumCatalystHCID 887MethanolSolventHCID 8028TetrahydrofuranSolvent

Procedure

A solution of 5-nitrobenzimidazole (3.0 g, 18.4 mmol) in 100 ml of THF was stirred with NaH (2.7 g, 36.8 mmol) for 0.5 h at 25° C. To the solution was added methyl iodide (2.0 ml, 20.3 mmol) and resulting mixture was stirred for 12 h. The reaction mixture was concentrated in vacuo to provide an oil, which was dissolved in 200 ml of MeOH and stirred with 0.3 g of 10% Pd/C under H2 for 12 h. The reaction mixture was filtered and concentrated in vacuo, yielding a dark oily residue which was subjected to column chromatography (3% MeOH/CHCl,) to provide 0.69 g (3.9 mmol, 21%) of 1-methyl-5-aminobenzimidazole and 0.36 g (2.0 mmol, 11%) of 3-methyl-5-aminobenzimidazole.

Workup

  1. customresulting mixture
  2. concentrationThe reaction mixture was concentrated in vacuo
  3. customto provide an oil, which
  4. filtrationThe reaction mixture was filtered
  5. concentrationconcentrated in vacuo
  6. customyielding a dark oily residue which

Sources & evidence

ORD record
ord-f0d9e99831314bcaa7e56358e2d320ce
Source dataset
uspto-grants-2002_08
Patent number
US06436982B1

Reaction notes

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